Method of making tubing.



A. s. MACDONALD. METHOD OF MAKING TUBING. APPLICATION FILED SEPT. 7. I916.

Patented Nov. 11, 1919.

III r 1 ing tubin mews s. MACDONALD, or GREAT NECK STATION, new YonK.

METHOD or MAKING Teams.

Specification of Letters Patent. Patented Nov, 11, 1919.

Application filed September 7, 1916, I Serial No. 118,800.

Be it known that I, ANGUS S. MACDONALD, of Great Neck Station, county of Nassau, and State of New York, have invented oer tain new and useful Improvements in Methods of Making Tubing, of which the following is a specification. j

his invention relates to a method of makand has for its primary object the provision ofan improved method which is simple in character, and economical in operationand which secures uniformity and superiority of product.

The foregoing, together with such other objects as may hereinafter appear, or are incident to my invention, I attain by means of a method and apparatus illustrated in the accompanying drawing wherein:

Figure-1 is a longitudinal section through a draw benchshowing one of the steps of my improved process; andF'igs. 2 and 3 are apparatus in difierent positions.

sectional views illustrating the, parts of the The invention is particularly useful in connection with tube drawing manufacture, and it contemplates a heattreatment of the metal under control, and in such manner as ,1051011, and warping and distortion,

as the elimination of'certain' steps in the to eliminate the-formation of scale or coras well customary methods pursued in manufacturing drawn tubin .which involve considerable delay and la%or. f

In the manufacture of drawn tubing it is customary to heat and pierce thelbillet and pass it a number of times through dies hot or in cold condition,

in order to form a tube,

and thereafter the tube is given a number of passes either in and the present mvention has to do primarily with the final steps in the formation of the tube. For exunder tension, as

ample, afterthe tube is given last pass, and while it is still in the draw bench, and will befurther pointed out, I simultaneously heat all of the metal to a uniform temperature and eliminate the strains which are incident to the drawing process, particularly where the tube is cold drawn. I accomplish this by attaching a air ofremovable terminals to trio current through the tube, the internalv I cool the metal by quenching or cooling baths,

the tube ad: acent the ends thereof and passing an elecchain and the power means have not been shown, but 1t Wlll be understood that such means has been utilized in drawing the tube 7 throughthe die 8, suitably mounted at one end of the draw bench, and over the mandrel 9, which is supported in any suitable manner, as by a draw bench extension (not shown); After the tube has thus been drawn, I provide a compensating means for placing the draw jaws 10' under tension, so that the tube 7, while placed under tension, may nevertheless freely expand without warping and distortion during the heating step, and likewise contract when the metal'is quenched. As one means for securing this result I employ a heavy weight 11' which is adapted to be attached to the draw jaws 10 by means pulley 13. Two removable terminals or pole membersM- and 15 are detachably fastened on the tube 7, adjacent the ends thereof, and current is passed through the tube 7 from a dynamo 16 or other suitable source of current, through a transformer 17 Con trol of the heat is obtained in any suitable of acable 12"passing over a lowered into the position shown in Fig. 2.

A quenching element, such as oilissupplied by this tubular framework in such manner as to make a substantially umform applica- "tion of the quenching material to the tube.

From the foregoing it willbe seen that my improved process may be briefly summarized as follows; After the tube has been drawn and while it is under a 'compensat- :in'g tension, it is uniformly heated throughout, the heat being entirely under ntrol, and then it is quenched and tempere after which the tube may be cut off andis in finished condition. By this improved process, I avoid the necesity of'removing the tube to a heatin furnace, in .w applied, and which is therefore not uniformly applied. The heatin in addition to eliminating the strains of t e drawing op- 'ch heat is externally- 7 materials.

eration," prevents the. formation of scale and oxldation and consequent metal losses because of the short period required for the heating, and at the same time warping or distortion is likewise prevented. Since the heating is entirely under control, and since the heating unlform throughout the tube,

it will beseen that uniformity of product is secured, the'superiority of the product be necessity for removal to a heating furnace,

I am enabled to dispense with the pickling baths which are necessary to remove scale and'corrosion. M

carbonization of t e metal.

- It will be obvious that in certain cases it may be desirable to heat and quench the metal previous tothe last pass, and also that various modifications of the method dition to obviating the process also prevents de-' and also of the particular apparatus shown and described may be made without departing from the spirit of my invention asset forth, in the claims, as for example the die and draw jaws may be utilized as the terminals and cooled by water or other means. It will also be apparent that my invention is equally appllcable to the drawing of steel in other forms, such as rods and bars,- and therefore that the term tubing employed herein is used in a broad sense.

I claim:

1. The process which consists in drawing a tube, placing it under tension and heating it, cutting off the heat, and while under tenslon quenching it in situ.

2. The herein described process of makin tubes which consists in drawing a tube, in heating all portions of the tube substantially simultaneously and uniformly while in the drawing apparatus, in quenching'the tube i/n. situ, and in removing the tube.

' Intestimony signed my name.

ANGUS s. MACDONALD.

whereof, I have hereunto 

